AUTOMATIC OPTICAL OUTPUT CONTROLLING CIRCUIT AND A PEAK LEVEL COMPARATOR-USING A MONITOR PHOTODIODE

摘要

PURPOSE: An automatic optical output controlling circuit and an optical output peak level comparator are provided to process data at high data processing rate by using slow elements. CONSTITUTION: An optical output peak level comparator is used in an automatic optical output controlling circuit using a monitor photo diode. The peak level comparator includes a voltage detector(241) and a voltage comparator(242). The voltage detector detects an output voltage from an optical current outputted from the monitor photo diode based on a clock signal synchronized with a burst data packet. The voltage comparator compares a magnitude of the detected output voltage with a predetermined reference voltage to output a voltage control signal.